Letter to the Faculty : 2010 : 11 : 02

Fall letter to the faculty from the Regional Vice Chancellor for Academic Affairs

Variations of plasma enzymes in the pony and the dog after carbon-tetrachloride administration.

Adult female dogs or pony mares were subjected to a nonlethal dose of CCl4 (0.5 ml/kg body wt). Amounts of several plasma enzymes thought to be indicative of hepatic disease were monitored. Plasma enzymes alanine aminotransferase, aspartate aminotransferase (AST), alkaline phosphatase (ALP), arginase, gamma-glutamyltransferase (GGT) and iditol dehydrogenase (ID) and total plasma bilirubin were determined in these animals before and after the administration of CCl4. In the dog, GGT was not significantly increased but ALP values increased during days 1-6. In the pony, GGT was significantly increased during the entire course of the study but ALP exhibited only small, transient (though significant) increases. Responses of ID, AST and ALP were unremarkable when compared between the pony and dog. Total bilirubin significantly (P .ltoreq. 0.05) increased from days 1-4 (pony) or days 5-8 (dog) after CCl4 dose but returned to or decreased below base-line values. Animals did not have evidence of icterus at any time. The dog and pony were distinct clinical entities and only the appropriate laboratory tests for each species should be used to provide information for the clinicopathologic evaluation of hepatic disease

Letter to the Faculty : 2010 : 04 : 15

Spring letter to the faculty from the Regional Vice Chancellor for Academic Affairs

Letter to the Faculty : 2009 : 01 : 30

Spring letter to the faculty from the Regional Vice Chancellor for Academic Affairs

Variations of plasma enzymes in the pony and the dog after carbon-tetrachloride administration.

Adult female dogs or pony mares were subjected to a nonlethal dose of CCl4 (0.5 ml/kg body wt). Amounts of several plasma enzymes thought to be indicative of hepatic disease were monitored. Plasma enzymes alanine aminotransferase, aspartate aminotransferase (AST), alkaline phosphatase (ALP), arginase, gamma-glutamyltransferase (GGT) and iditol dehydrogenase (ID) and total plasma bilirubin were determined in these animals before and after the administration of CCl4. In the dog, GGT was not significantly increased but ALP values increased during days 1-6. In the pony, GGT was significantly increased during the entire course of the study but ALP exhibited only small, transient (though significant) increases. Responses of ID, AST and ALP were unremarkable when compared between the pony and dog. Total bilirubin significantly (P .ltoreq. 0.05) increased from days 1-4 (pony) or days 5-8 (dog) after CCl4 dose but returned to or decreased below base-line values. Animals did not have evidence of icterus at any time. The dog and pony were distinct clinical entities and only the appropriate laboratory tests for each species should be used to provide information for the clinicopathologic evaluation of hepatic disease

Effect of TLCK on transcription and its role in modifying cell-growth.

The synthetic protease inhibitor N-tosyl-L-lysine-chloromethyl ketone (TLCK) acts to inhibit transcription when added to cell lines growing in vitro. This inhibition of transcription is most pronounced in transformed cells where TLCK is very toxic at concentrations as low as 25 mug/ml of culture medium. Non-transformed cells are more resistant to the effect of TLCK, requiring ten times more TLCK to produce a comparable inhibition of transcription. The effect of this protease inhibitor on transcription can be prevented by preincubation of the cells in reduced glutathione or cysteine; however, the cells can not be rescued from the effect of TLCK even if glutathione or cysteine are added to the culture medium within five minutes of the addition of TLCK

Nuclear-envelope of Chinese-hamster ovary cells - re-formation of the nuclear-envelope following mitosis.

We have developed a technique for isolating nuclei and nuclear envelope(s) (NE) from Chinese hamster ovary (CHO) cells which does not depend on the use of detergents to solubilize contaminating cytoplasm. In our procedure NE are prepared from purified nuclei by nuclease digestion and subsequent high salt-sucrose gradient centrifugation. The nuclei and NE fractions are free of significant contamination by other subcellular organelles as judged by electron microscopy and enzyme analysis. Examination of the peptide and glycopeptide composition of the NE fraction by sodium dodecyl sulfate-polyacrylamide gel electrophoresis reveals a very complex coomassie blue staining profile with prominent bands in the 55 000-75 000 molecular weight range. Using this NE isolation technique, we have examined the breakdown and re-formation of the NE during a limited stage (late G2, M, and early G1) of the replicative cycle in synchronized populations of CHO cells. Our data demonstrate that a minimum of 60% of the early G1 NE protein and a minimum of 50% of the early G1 NE phospholipid were present in the cell during the preceding G2 phase of the cell cycle and were reutilized in the re-formation of the NE occurring during late M and early G1. Our evidence suggests that the vast majority of the newly synthesized peptides and glycopeptides of the NE which appear in the daughter NE are synthesized during the early G1 phase of the replicative cycle. Examination of the NE peptides by one-dimensional gel electrophoresis suggests that no reproducible changes in NE peptide composition can be correlated with specific phases of the cell cycle

Liver tests in dogs receiving anticonvulsant drugs (diphenylhydantoin and primidone).

Two groups of adult female dogs were given diphenylhydantoin or primidone orally for 82 days. Plasma glutamic-pyruvic transaminase (GPT), alkaline phosphatase (AP) and gamma-glutamyl transferase (GGT) activity, total plasma bilirubin (TBR) concentration, fasting bile acid level and percent sulfobromophthalein (% BSP) retention were determined in the dogs prior to and after treatment. Plasma GPT and AP showed persistent increases in some dogs, while occasional increases occurred in the remaining dogs in both groups. The plasma enzymes returned to normal 5 wk after treatment. Plasma GGT, TBR, fasting bile acids and % BSP retention were normal during the study